1. Field of the Invention
The present invention relates to a passenger airbag apparatus adapted to be mounted in front of a front passenger's seat of a vehicle.
2. Description of Related Art
As disclosed in JP 2009-179156 A and JP 2001-270411 A, a known passenger airbag apparatus includes an airbag, an inflator formed into a cylinder for supplying the airbag with an inflation gas and a case made of sheet metal, for housing the airbag and inflator.
In an airbag apparatus disclosed in the former reference, the inflator is secured to the case through the use of a stopper plate that is welded to the case and a securing fixture that is bolt fixed to the case. The stopper plate receives a non-cylindrical, deformed shaft of a first end of the inflator and prevents the shaft center of the inflator from rotating in a circumferential direction. The stopper plate and the securing fixture, which is located to face a second end of the inflator, fix the positions of the end planes of the inflator and prevent the inflator from moving in an axial direction. With this configuration, however, the securing fixture has to be attached to the case in addition to a retainer for securing an airbag to the case, which increases a number of parts of the apparatus as well as a number of processes of mounting the inflator on the case.
In an airbag apparatus of the latter reference, the inflator has a mounting bolt at a first end and a large flange at a second end. A case includes a large opening and a small opening such that the inflator penetrates through those openings to be set in the case. At mounting of the inflator, specifically, the first end of the inflator having the mounting bolt is inserted through the large opening until the bolt reaches the small opening and protrudes out of there whereas the flange abuts against the periphery of the large opening. The mounting bolt is nut fastened such that the inflator is assembled with the case. The inflator in the former reference is mounted on the case in a similar fashion as well. However, this mounting fashion requires a confirmation whether the leading end of the inflator finally protrudes out of the case, and the confirmation complicates the mounting work.